1. Field of the Invention
This invention relates to a vial access adapter connectable to a vial which contains a medical fluid therein and is closed by an elastomeric stopper, wherein the vial access adapter is provided with a dual spike, one for withdrawing the medical fluid from the vial, and the other for simultaneous entry of air into the vial.
2. Reported Developments
Vials made of glass or polymeric materials, the walls of which are non-collapsible, require an air inlet when medical fluid is withdrawn therefrom to prevent the formation of vacuum therein. Typically, vials containing a medical fluid are closed by rubber stoppers which are pierced by a dual spike having a medical fluid passage and an air inlet passage, therein. The air inlet passage contains a filter to prevent entry of particulate matter or bacteria into the vials during the medicament withdrawal process.
The prior art has provided devices comprising a liquid flow passage and an air flow passage, such as disclosed, for example, in U.S. Pat. Nos. 3,359,977, 3,608,550, 3,783,895, 4,262,671, 4,505,709, 4,588,403, 4,787,898, 5,358,501, and 5,636,660. These inventions have advanced the prior art by providing convenient adapters and transfer devices connectable to containers of medical fluids.
In addition to providing in a vial access adapter a dual spike for withdrawing a medical fluid from a vial and simultaneously introducing filtered atmospheric air into the vial, the present invention also provides an elastomeric seal positioned in the fluid passage flow of the dual spike for hermetically sealing the fluid flow passage. In a preferred embodiment the elastomeric seal is of an M-shaped configuration through which the medical fluid can be accessed repeatedly. After each withdrawal of the desired amount the medical fluid the elastomeric seal reseals itself thereby preventing contamination of the medical fluid by air-born particles, such as dust and bacteria.
A further improvement in the present invention over the prior art is the spatial configuration of the medical fluid access spike which, on positioning of the vial access adapter over a vial having a rubber stopper, penetrates the rubber stopper and just clears the bottom surface of the rubber stopper. This spatial configuration allows essentially complete withdrawal of the medical fluid contained in the vial.
In accordance with the present invention, there is provided a vial access adapter for use with a glass vial or a rigid or semi-rigid polymeric vial containing a liquid medicament, diagnostic agent, or nutritional formulation therein. In the first embodiment of the present invention the vial access adapter body comprises:
a horizontal top wall having a plurality of vent holes therein;
a horizontal second wall spaced parallel from the horizontal top wall;
a cylindrical side wall integral with the horizontal top wall and the horizontal second wall enclosing a chamber therebetween and extending downward from the horizontal second wall forming a skirt and terminating in a bottom rim;
a first spike centrally located in the vial access adapter body having a top portion extending above the horizontal wall and terminating in an externally threaded luer connector, and a bottom portion extending downward and terminating in a sharp point;
a fluid flow channel in the first spike designed for carrying the liquid medicament;
a second spike positioned parallel to the first spike extending downward from the horizontal second wall and terminating in a sharp point;
an air flow channel in the second spike designed for air flow from the chamber between the horizontal top wall and the horizontal second wall into the vial during withdrawal of the liquid medicament from the vial; and
an elastomeric membrane within the luer connector for sealing the fluid flow channel.
Preferably, the elastomeric membrane reseals itself upon repeated penetration by an external luer connector and allows repeated withdrawal of the liquid medicament from the vial without risk of contamination from atmospheric environment.
In the second embodiment, the vial access adapter body comprises:
a vertical cylindrical side wall having a top portion terminating in a top rim, and a skirt portion extending downward from the top rim and terminating in a bottom rim;
a horizontal, circular wall enclosing the top portion of the cylindrical side wall and is located slightly below the top rim forming a disc-shaped chamber with the top rim;
a disc-shaped anti-bacterial filter positioned in the disc-shaped chamber;
a removable retaining disc for the anti-bacterial filter positioned on top of the anti-bacterial filter and having a plurality of vent holes therein;
a pair of spikes integral with each other and centrally located in the vial access adapter body: the first spike of the pair having a top portion extends above the horizontal, circular wall and the and the removable retaining disc terminating in an externally threaded luer connector and the bottom portion extending downward and terminating slightly below the bottom rim of the cylindrical side wall; and the second spike of the pair extends from the horizontal, circular wall downward to the bottom rim of the cylindrical side wall and terminating slightly below the bottom rim of the cylindrical side wall, wherein the pair of spikes together terminate in a sharp point;
a fluid flow channel in the first spike of the pair designed to carry a liquid medicament;
an air flow channel in the second spike of the pair designed for outside air flow from the disc-shaped chamber through the anti-bacterial filter into the vial during withdrawal of the liquid medicament from the vial; and
an elastomeric membrane within the luer connector of the first spike of the pair for sealing the fluid flow channels.
Preferably, the elastomeric membrane reseals itself upon repeated penetration by an external luer connector and allows repeated withdrawal of the liquid medicament from the vial without risk of contamination from atmospheric environment.
This embodiment of the present invention wherein the pair of spikes are centered ensures alignment with the external luer connector and prevents buckling of the spikes upon insertion into the a rubber stopper.